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sfdownhill last won the day on June 19

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About sfdownhill

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  • Birthday 04/14/1964

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  • Location
    Vista CA
  • In My Garage:
    2001 VFR
    2010 Aprilia RSV4 track bike
    2003 CRF450R

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  1. I hear ya - the faster you go two-up, the more visceral the helmet bumping becomes...
  2. Wow Sparkie - that’s an impressive number of miles. As detailed in his post above, Flya750 makes use of Power Commander’s map switching option - a simple handlebar-mounted switch changes between two fueling maps. In Flya750’s case he toggles at will between the stock fueling map and a performance-tuned map; between effiency and performance. Badger1 below you can see a full system: WiLD headers (WiLD is a nickname donated by a VFRD member) and a high mount muffler. In this case, we used an existing Yoshimura canister, but cut it down a few inches shorter than it came from Yosh. Fitt
  3. We don’t see ponying up for extra sets of headers as a feasible option. We’re checking to see if the tube-bending guy might get started on our current order if he gets paid for bending 15 sets, but only has to bend tubes for ~ 10 sets.
  4. Hey Skids - just saw the photo of your VFR1200 on your profile - beautiful motorbike! On fuel economy, we don’t have it so bad w our VFRs, even with the headers and a fuel-generous tune. I just did a big airbox/velocity stack mod on my RVS4 and dropped in a race tuned map (w quick shift and autoblip - heheh) - now the fuel warning light comes on around 70 miles into a full tank and I’d better pull in by 95 miles or I’ll be stranded trackside. ‘Course the tank is only 3.5 gallons, but still.
  5. Here are two versions of the 8 gen dyno chart. The graphs were both generated on the same day, on the same dyno, by the same dyno tech. The professional VFRD crew did the exhaust swap in the Attack parking lot, and the dyno work was all done by Jozef at Attack Performance in Huntington Beach CA. Attack is the top race shop in California - they run the Attack Performance Yamaha factory superbike race team, with riders Cameron Beaubier [2020 MotoAmerica superbike champion] and Jake Gagne [2nd in the 2020 MotoAmercia superbike championship]. Each dyno chart has three graph lines:
  6. We proposed to Wade that we’d consider paying his mandrel tube-bending subcontractor the total amount for bending his minimum order of 15 sets even though we’d only be purchasing 10 sets. Thanks to VFRD member Dangeruss for this creative potential solution. The minimum order is the bender’s requirement, not Wade’s. The response was a bit cryptic, so we are continuing the conversation in an attempt to get a clear answer.
  7. Any chance of putting up the Dyno charts for the headers please fink - later tonight, when back to my laptop, I’ll post the 8 gen before-and-after dyno sheets here so you won’t have to sift through the behemoth header thread to find them.
  8. Yeah you do! I was not ready to have my 5th gen mind changed, but when I rode a deluxe model 8 gen...
  9. Mello dude - thanks for the props and link. Badger1, there’s a deep deep ocean of info in that header thread - probably too much. I say that even though - or maybe because - I am co-culprit w VFRD member Duc2V4 on the whole header ride. In a nutshell, the headers in the thread linked by mello dude make significant improvement to torque and horsepower, especially in the midrange 7000-10000rpm where we have the most fun on our VFRs. The headers make an even more dramatic improvement on the 8 gen than they do on 5 or 6 gens. The 8 gen benefits most because Honda speci
  10. Great questions all, but somewhere in there, some combination of my knowledge, experience and authority has been exceeded - lol - I have a heavy underpowered 5 gen with Power Commander! (Really all VFRs under 1200cc’s are underpowered - see exceptions below) Look up threads/posts by VFRD member Mohawk - I believe he is the VFR weight loss champion having lost ~ 34kg off his 5 gen (Absolutely apologize, HighSideNZ, if I’ve got that wrong and your 6 gen is skinniest!). HighSideNZ, Mohawk, and CandyRedRC46 all come to mind when I think of the horsepower brokers on this foru
  11. Duc2V4 has Rapid Bike (RB) with autotune on both his 5 gen with the WiLD headers and his 6 gen w 98/99 catless headers - he is so pleased with the RB autotune performance on both bikes that he hasn’t done any dyno tuning (yet). We have both looked into dyno tuning w RB, but, like you, haven’t come across the ‘how to’ guide. Seems RB is designed more for letting the autotune make changes and develop mapping for the air/fuel ratio (AFR) the operator selects.
  12. Hi Jim, I believe the 6 gen map we sent you is a good starting point, though custom dyno tuning done on your own VFR may yield slight improvement. A second map for race fuel is definitely viable, and PCV does provide for a handlebar mounted switch for selecting between maps. The O2 sensors you want are wideband, usually Bosch (Available from Dynojet and others) and have standard M18 18mm threads (M18x1.5 if I recall correctly). Installation of the headers on 6 gen does require a bit of trimming to the heat shield attached the the rear fender at the back of t
  13. We are currently at 9 deposited orders for 5/6 gen headers and 2 deposited orders for 8 gen headers. We are working on getting Wade (the fabricator) to combine the two configurations toward the minimum order of 15 units.
  14. Greetings all, I'm just back from 5 weeks at the far end of a 40 mile long lake in Washington state [Lake Chelan] and am very grateful to Duc2V4 for keeping up with the communications while I've been off the map. Duc has also been maintaining and updating the master spreadsheet of all deposits received and orders placed for headers. I currently have 72 VFRD notifications to attend to; this post begins the next step of burrowing into the task of catching up on this thread and responding to all PMs. I'll briefly review the latest PMs for breaking news, then start at the c
  15. Flya, you’ve hit on the difficulty in interpreting dyno charts - what do they mean to the way a motorcycle actually rides? If one is lucky enough to take the two motorcycles in question - Hammerdrill’s 6 gen and Samuelx’s 8 gen - out for a 100 miles or so that includes a bit of city surface streets, a bit of freeway, and healthy helping of one’s favorite twisty roads (I was exactly this lucky), the conclusion drawn would actually be that the 8 gen has more power, and certainly more grunt. This impression comes from the midrange, and my subjective opinion Is that unless we are riding our VFRs
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